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Clinical Translation of Microbiome Research in Alopecia Areata: A New Perspective? COSMETICS 2022. [DOI: 10.3390/cosmetics9030055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
The continuous research advances in the microbiome field is changing clinicians’ points of view about the involvement of the microbiome in human health and disease, including autoimmune diseases such as alopecia areata (AA). Both gut and cutaneous dysbiosis have been considered to play roles in alopecia areata. A new approach is currently possible owing also to the use of omic techniques for studying the role of the microbiome in the disease by the deep understanding of microorganisms involved in the dysbiosis as well as of the pathways involved. These findings suggest the possibility to adopt a topical approach using either cosmetics or medical devices, to modulate or control, for example, the growth of overexpressed species using specific bacteriocins or postbiotics or with pH control. This will favour at the same time the growth of beneficial bacteria which, in turn, can impact positively both the structure of the scalp ecosystem on the host’s response to internal and external offenders. This approach, together with a “systemic” one, via oral supplementation, diet, or faecal transplantation, makes a reliable translation of microbiome research in clinical practice and should be taken into consideration every time alopecia areata is considered by a clinician.
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Abstract
Human skin forms a protective barrier against the external environment and is our first line of defense against toxic, solar, and pathogenic insults. Our skin also defines our outward appearance, protects our internal tissues and organs, acts as a sensory interface, and prevents dehydration. Crucial to the skin's barrier function is the colonizing microbiota, which provides protection against pathogens, tunes immune responses, and fortifies the epithelium. Here we highlight recent advances in our understanding of how the microbiota mediates multiple facets of skin barrier function. We discuss recent insights into pathological host-microbiota interactions and implications for disorders of the skin and distant organs. Finally, we examine how microbiota-based mechanisms can be targeted to prevent or manage skin disorders and impaired wound healing.
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Affiliation(s)
- Tamia A Harris-Tryon
- Department of Dermatology, University of Texas Southwestern Medical Center, Dallas, TX, USA
| | - Elizabeth A Grice
- Departments of Dermatology and Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
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53
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Crosstalk between Body Microbiota and the Regulation of Immunity. J Immunol Res 2022; 2022:6274265. [PMID: 35647199 PMCID: PMC9135571 DOI: 10.1155/2022/6274265] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 04/19/2022] [Accepted: 04/25/2022] [Indexed: 11/26/2022] Open
Abstract
The microbiome corresponds to the genetic component of microorganisms (archaea, bacteria, phages, viruses, fungi, and protozoa) that coexist with an individual. During the last two decades, research on this topic has become massive demonstrating that in both homeostasis and disease, the microbiome plays an important role, and in some cases, a decisive one. To date, microbiota have been identified at different body locations, such as the eyes, lung, gastrointestinal and genitourinary tracts, and skin, and technological advances have permitted the taxonomic characterization of resident species and their metabolites, in addition to the cellular and molecular components of the host that maintain a crosstalk with local microorganisms. Here, we summarize recent studies regarding microbiota residing in different zones of the body and their relationship with the immune system. We emphasize the immune components underlying pathological conditions and how they interact with local (and distant) microbiota.
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54
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The Regulatory-T-Cell Memory Phenotype: What We Know. Cells 2022; 11:cells11101687. [PMID: 35626725 PMCID: PMC9139615 DOI: 10.3390/cells11101687] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Revised: 05/11/2022] [Accepted: 05/17/2022] [Indexed: 01/25/2023] Open
Abstract
In immunology, the discovery of regulatory T (Treg) cells was a major breakthrough. Treg cells play a key role in pregnancy maintenance, in the prevention of autoimmune responses, and in the control of all immune responses, including responses to self cells, cancer, infection, and a transplant. It is currently unclear whether Treg cells are capable of long-term memory of an encounter with an antigen. Although the term “immunological memory” usually means an enhanced ability to protect the body from reinfection, the memory of the suppressive activity of Treg cells helps to avoid the state of generalized immunosuppression that may result from the second activation of the immune system. In this review, we would like to discuss the concept of regulatory memory and in which tissues memory Treg cells can perform their functions.
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55
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Abstract
Our skin is the interface through which we mediate lifelong interactions with our surrounding environment. Initial development of the skin's epidermis, adnexal structures, and barrier function is necessary for normal cutaneous microbial colonization, immune development, and prevention of disease. Early life microbial exposures can have unique and long-lasting impacts on skin health. The identity of neonatal skin microbes and the context in which they are first encountered, i.e., through a compromised skin barrier or in conjunction with cutaneous inflammation, can have additional short- and long-term health consequences. Here, we discuss key attributes of infant skin and endogenous and exogenous factors that shape its relationship to the early life cutaneous microbiome, with a focus on their clinical implications.
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Affiliation(s)
- Laura R Dwyer
- Department of Dermatology, University of California, San Francisco, San Francisco, CA, USA; Biomedical Sciences Graduate Program, University of California, San Francisco, San Francisco, CA, USA
| | - Tiffany C Scharschmidt
- Department of Dermatology, University of California, San Francisco, San Francisco, CA, USA.
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56
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Estrada Brull A, Panetti C, Joller N. Moving to the Outskirts: Interplay Between Regulatory T Cells and Peripheral Tissues. Front Immunol 2022; 13:864628. [PMID: 35572535 PMCID: PMC9099010 DOI: 10.3389/fimmu.2022.864628] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Accepted: 03/25/2022] [Indexed: 12/12/2022] Open
Abstract
Regulatory T cells (Tregs) restrain excessive immune responses and dampen inflammation. In addition to this classical immune suppressive role, Tregs in non-lymphoid tissues also promote tissue homeostasis, regeneration and repair. In this review, we outline our current understanding of how Tregs migrate to peripheral tissues and the factors required for their maintenance at these sites. We discuss the tissue-specific adaptations of Tregs at barrier and immuno-privileged sites and the mechanisms that regulate their function within these organs. Furthermore, we outline what is known about the interactions of Tregs with non-immune cells in the different peripheral tissues at steady state and upon challenge or tissue damage. A thorough understanding of the tissue-specific adaptations and functions of Tregs will potentially pave the way for therapeutic approaches targeting their regenerative role.
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57
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Skin immunity: dissecting the complex biology of our body's outer barrier. Mucosal Immunol 2022; 15:551-561. [PMID: 35361906 DOI: 10.1038/s41385-022-00505-y] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Revised: 03/10/2022] [Accepted: 03/11/2022] [Indexed: 02/04/2023]
Abstract
Our skin contributes critically to health via its role as a barrier tissue, carefully regulating passage of key substrates while also providing defense against exogenous threats. Immunological processes are integral to almost every skin function and paramount to our ability to live symbiotically with skin commensal microbes and other environmental stimuli. While many parallels can be drawn to immunobiology at other mucosal sites, skin immunity demonstrates unique features that relate to its distinct topography, chemical composition and microbial ecology. Here we provide an overview of skin as an immune organ, with reference to the broader context of mucosal immunology. We review paradigms of innate as well as adaptive immune function and highlight how skin-specific structures such as hair follicles and sebaceous glands interact and contribute to these processes. Finally, we highlight for the mucosal immunology community a few emerging areas of interest for the skin immunity field moving forward.
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58
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Hwang J, Rick J, Hsiao J, Hamzavi IH, Shi VY. Microbiome in Hidradenitis Suppurativa: Current Evidence and Practice. CURRENT DERMATOLOGY REPORTS 2022. [DOI: 10.1007/s13671-021-00349-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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59
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Lee J, Kim D, Min B. Tissue Resident Foxp3+ Regulatory T Cells: Sentinels and Saboteurs in Health and Disease. Front Immunol 2022; 13:865593. [PMID: 35359918 PMCID: PMC8963273 DOI: 10.3389/fimmu.2022.865593] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2022] [Accepted: 02/22/2022] [Indexed: 01/04/2023] Open
Abstract
Foxp3+ regulatory T (Treg) cells are a CD4 T cell subset with unique immune regulatory function that are indispensable in immunity and tolerance. Their indisputable importance has been investigated in numerous disease settings and experimental models. Despite the extensive efforts in determining the cellular and molecular mechanisms operating their functions, our understanding their biology especially in vivo remains limited. There is emerging evidence that Treg cells resident in the non-lymphoid tissues play a central role in regulating tissue homeostasis, inflammation, and repair. Furthermore, tissue-specific properties of those Treg cells that allow them to express tissue specific functions have been explored. In this review, we will discuss the potential mechanisms and key cellular/molecular factors responsible for the homeostasis and functions of tissue resident Treg cells under steady-state and inflammatory conditions.
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Affiliation(s)
- Juyeun Lee
- Department of Cardiovascular and Metabolic Sciences, Lerner Research Institute, Cleveland Clinic, Cleveland, OH, United States
| | - Dongkyun Kim
- Department of Microbiology and Immunology, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
| | - Booki Min
- Department of Microbiology and Immunology, Feinberg School of Medicine, Northwestern University, Chicago, IL, United States
- *Correspondence: Booki Min,
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60
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Swaney MH, Kalan LR. Two-for-one: Dual host-microbe functions of S. epidermidis Sph. Cell Host Microbe 2022; 30:279-280. [PMID: 35271798 DOI: 10.1016/j.chom.2022.02.011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
The skin microbiome is essential for skin function, yet the mechanisms responsible are only beginning to be uncovered. In this issue of Cell Host & Microbe, Zheng et al. demonstrate that a Staphylococcus epidermidis sphingomyelinase has a mutually beneficial role in supporting the skin barrier and promoting S. epidermidis colonization.
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Affiliation(s)
- Mary Hannah Swaney
- Department of Medical Microbiology and Immunology, School of Medicine and Public Health, University of Wisconsin, Madison, WI, USA
| | - Lindsay R Kalan
- Department of Medicine, School of Medicine and Public Health, University of Wisconsin, Madison, WI, USA.
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61
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Lousada MB, Lachnit T, Edelkamp J, Paus R, Bosch TCG. Hydra and the hair follicle - An unconventional comparative biology approach to exploring the human holobiont. Bioessays 2022; 44:e2100233. [PMID: 35261041 DOI: 10.1002/bies.202100233] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 02/02/2022] [Accepted: 02/17/2022] [Indexed: 12/14/2022]
Abstract
The microbiome of human hair follicles (HFs) has emerged as an important player in different HF and skin pathologies, yet awaits in-depth exploration. This raises questions regarding the tightly linked interactions between host environment, nutrient dependency of host-associated microbes, microbial metabolism, microbe-microbe interactions and host immunity. The use of simple model systems facilitates addressing generally important questions and testing overarching, therapeutically relevant principles that likely transcend obvious interspecies differences. Here, we evaluate the potential of the freshwater polyp Hydra, to dissect fundamental principles of microbiome regulation by the host, that is the human HF. In particular, we focus on therapeutically targetable host-microbiome interactions, such as nutrient dependency, microbial interactions and host defence. Offering a new lens into the study of HF - microbiota interactions, we argue that general principles of how Hydra manages its microbiota can inform the development of novel, microbiome-targeting therapeutic interventions in human skin disease.
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Affiliation(s)
- Marta B Lousada
- Monasterium Laboratory Skin & Hair Research, Münster, Germany.,Zoological Institute, Christian-Albrechts, University of Kiel, Kiel, Germany
| | - Tim Lachnit
- Zoological Institute, Christian-Albrechts, University of Kiel, Kiel, Germany
| | - Janin Edelkamp
- Monasterium Laboratory Skin & Hair Research, Münster, Germany
| | - Ralf Paus
- Monasterium Laboratory Skin & Hair Research, Münster, Germany.,Dr. Phillip Frost Department of Dermatology & Cutaneous Surgery, University of Miami Miller School of Medicine, Miami, Florida, USA
| | - Thomas C G Bosch
- Zoological Institute, Christian-Albrechts, University of Kiel, Kiel, Germany
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62
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Chen B, Yang J, Song Y, Zhang D, Hao F. Skin Immunosenescence and Type 2 Inflammation: A Mini-Review With an Inflammaging Perspective. Front Cell Dev Biol 2022; 10:835675. [PMID: 35281103 PMCID: PMC8908007 DOI: 10.3389/fcell.2022.835675] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 01/17/2022] [Indexed: 11/13/2022] Open
Abstract
Skin-resident stromal cells, including keratinocytes, fibroblasts, adipocytes, and immune cells including Langerhans cells, dendritic cells, T cells, and innate lymphoid cells, and their functional products work in concert to ensure the realization of skin barrier immunity. However, aging-induced immunosenescence predisposes the elderly to pruritic dermatoses, including type 2 inflammation-mediated. Inflammaging, characterized by chronic low level of pro-inflammatory cytokines released from senescent cells with the senescence-associated secretory phenotype (SASP), may drive immunosenescence and tangle with type 2 inflammatory dermatoses. The present mini-review summarizes current evidence on immunosenescence and type 2 inflammation in the skin and further focuses on future needs from an inflammaging perspective to clarify their complexity.
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Affiliation(s)
- Bangtao Chen
- Department of Dermatology, Chongqing University Three Gorges Hospital, School of Medicine, Chongqing University, Chongqing, China
| | - Jing Yang
- Department of Dermatology, Chongqing University Three Gorges Hospital, School of Medicine, Chongqing University, Chongqing, China
| | - Yao Song
- Department of Dermatology, The Third Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Daojun Zhang
- Department of Dermatology, The Third Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Fei Hao
- Department of Dermatology, The Third Affiliated Hospital of Chongqing Medical University, Chongqing, China
- *Correspondence: Fei Hao,
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63
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Li C, Feng C, Ma G, Fu S, Chen M, Zhang W, Li J. Time-course RNA-seq analysis reveals stage-specific and melatonin-triggered gene expression patterns during the hair follicle growth cycle in Capra hircus. BMC Genomics 2022; 23:140. [PMID: 35172715 PMCID: PMC8848980 DOI: 10.1186/s12864-022-08331-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2021] [Accepted: 01/19/2022] [Indexed: 12/29/2022] Open
Abstract
Background Cashmere goat is famous for its high-quality fibers. The growth of cashmere in secondary hair follicles exhibits a seasonal pattern arising from circannual changes in the natural photoperiod. Although several studies have compared and analyzed the differences in gene expression between different hair follicle growth stages, the selection of samples in these studies relies on research experience or morphological evidence. Distinguishing hair follicle growth cycle according to gene expression patterns may help to explore the regulation mechanisms related to cashmere growth and the effect of melatonin from a molecular level more accurately. Results In this study, we applied RNA-sequencing to the hair follicles of three normal and three melatonin-treated Inner Mongolian cashmere goats sampled every month during a whole hair follicle growth cycle. A total of 3559 and 988 genes were subjected as seasonal changing genes (SCGs) in the control and treated groups, respectively. The SCGs in the normal group were divided into three clusters, and their specific expression patterns help to group the hair follicle growth cycle into anagen, catagen and telogen stages. Some canonical pathways such as Wnt, TGF-beta and Hippo signaling pathways were detected as promoting the hair follicle growth, while Cell adhesion molecules (CAMs), Cytokine-cytokine receptor interaction, Jak-STAT, Fc epsilon RI, NOD-like receptor, Rap1, PI3K-Akt, cAMP, NF-kappa B and many immune-related pathways were detected in the catagen and telogen stages. The PI3K-Akt signaling, ECM-receptor interaction and Focal adhesion were found in the transition stage between telogen to anagen, which may serve as candidate biomarkers for telogen-anagen regeneration. A total of 16 signaling pathways, 145 pathway mRNAs, and 93 lncRNAs were enrolled to construct the pathway-mRNA-lncRNA network, which indicated the function of lncRNAs through interacting with their co-expressed mRNAs. Pairwise comparisons between the control and melatonin-treated groups also indicated 941 monthly differentially expressed genes (monthly DEGs). These monthly DEGs were mainly distributed from April and September, which revealed a potential signal pathway map regulating the anagen stage triggered by melatonin. Enrichment analysis showed that Wnt, Hedgehog, ECM, Chemokines and NF-kappa B signaling pathways may be involved in the regulation of non-quiescence and secondary shedding under the influence of melatonin. Conclusions Our study decoded the key regulators of the whole hair follicle growth cycle, laying the foundation for the control of hair follicle growth and improvement of cashmere yield. Supplementary Information The online version contains supplementary material available at 10.1186/s12864-022-08331-z.
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Affiliation(s)
- Chun Li
- College of Animal Science and Technology, Inner Mongolia Minzu University, Tongliao, 028000, China
| | - Cong Feng
- College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Guangyuan Ma
- College of Life Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Shaoyin Fu
- Inner Mongolia Academy of Agricultural & Animal Husbandry Sciences, Hohhot, 010018, China
| | - Ming Chen
- College of Life Sciences, Zhejiang University, Hangzhou, 310058, China. .,College of Life Science and Food Engineering, Inner Mongolia Minzu University, Tongliao, 028000, China.
| | - Wenguang Zhang
- College of Animal Science, Inner Mongolia Agricultural University, Hohhot, 010018, China.
| | - Jinquan Li
- College of Animal Science, Inner Mongolia Agricultural University, Hohhot, 010018, China.
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64
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The Promising Role of Chemokines in Vitiligo: From Oxidative Stress to the Autoimmune Response. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2022; 2022:8796735. [PMID: 35096274 PMCID: PMC8791757 DOI: 10.1155/2022/8796735] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 12/09/2021] [Accepted: 12/20/2021] [Indexed: 12/12/2022]
Abstract
Vitiligo is a common chronic autoimmune skin disorder featured with depigmented patches and underlying destruction of melanocytes in the lesional skin. Multiple factors and mechanisms have been proposed for the etiopathogenesis of vitiligo, among which oxidative stress has been widely accepted as a key factor in initiating melanocyte loss. The altered redox status caused by oxidative stress, including the overproduction of reactive oxygen species (ROS) and the decreased activity of the antioxidant system in the skin, surrenders the resistance of melanocytes to exogenous or endogenous stimuli and eventually impairs the normal defense mechanism, leading to the absence of melanocytes. Considering the important role of innate and adaptive immunity in vitiligo, there is mounting evidence revealing an association between oxidative stress and autoimmunity. Since the significant changes of chemokines have been documented in vitiligo in many recent studies, it has been suggested that ROS-mediated chemotactic signals are not only the biomarkers of disease progression and prognosis but also are involved in the pathogenesis of vitiligo by facilitating the innate and adaptive immune cells, especially melanocyte-specific T cells, trafficking to the lesional areas of vitiligo. In this review, we discuss the interaction between oxidative stress and autoimmune response orchestrated by chemokines, including CXCL16-CXCR6 axis, CXCL9/CXCL10-CXCR3 axis, and other altered chemokines in vitiligo, and we also try to provide insight into potential therapeutic options through targeting these pathways.
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65
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Naik S. One Size Does Not Fit All: Diversifying Immune Function in the Skin. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2022; 208:227-234. [PMID: 35017212 PMCID: PMC8820520 DOI: 10.4049/jimmunol.2100758] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Accepted: 10/11/2021] [Indexed: 01/17/2023]
Abstract
Our body's most outward facing epithelial barrier, the skin, serves as the frontline defense against myriad environmental assailants. To combat these motley threats, the skin has evolved a sophisticated immunological arsenal. In this article, I provide an overview of the skin's complex architecture and the distinct microniches in which immune cells reside and function. I review burgeoning literature on the synchronized immune, stromal, epithelial, and neuronal cell responses in healthy and inflamed skin. Next, I delve into the distinct requirement and mechanisms of long-term immune surveillance and tissue adaptation at the cutaneous frontier. Finally, by discussing the contributions of immune cells in maintaining and restoring tissue integrity, I underscore the constellation of noncanonical functions undertaken by the skin immune system. Just as our skin's immune system benefits from embracing diverse defense strategies, so, too, must we in the immunology research community support disparate perspectives and people from all walks of life.
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Affiliation(s)
- Shruti Naik
- Department of Pathology, Department of Medicine, Ronald O. Perelman Department of Dermatology, and Perlmutter Cancer Center, New York University Langone Health, 550 First Avenue, New York, New York. 10016 USA,Correspondence to:
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66
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Pereira MS, Redanz S, Kriegel MA. Skin Deep: The Role of the Microbiota in Cutaneous Autoimmunity. J Invest Dermatol 2022; 142:834-840. [PMID: 35027173 DOI: 10.1016/j.jid.2021.12.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2021] [Revised: 12/05/2021] [Accepted: 12/06/2021] [Indexed: 12/16/2022]
Abstract
The skin microbiota is thought to possibly contribute to the pathogenesis of skin autoimmune diseases. The gut microbiota affects systemically the development and function of the immune system, thereby potentially influencing cutaneous autoimmunity as well. In this paper, we review the role of the gut and skin microbiota in cutaneous autoimmune diseases. Besides direct inflammatory effects at the skin barrier, microbiota may contribute to the pathogenesis of skin autoimmune diseases by metabolites, recall immune cell responses, and permeation of antigens to the subepidermal space. Skin and gut barrier dysfunction may represent a common pathophysiologic process allowing microbiota or its particles to promote autoimmune diseases at barrier surfaces.
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Affiliation(s)
- Márcia S Pereira
- Department of Translational Rheumatology and Immunology, Institute of Musculoskeletal Medicine, University of Münster, Münster, Germany
| | - Sylvio Redanz
- Department of Translational Rheumatology and Immunology, Institute of Musculoskeletal Medicine, University of Münster, Münster, Germany
| | - Martin A Kriegel
- Department of Translational Rheumatology and Immunology, Institute of Musculoskeletal Medicine, University of Münster, Münster, Germany; Section of Rheumatology and Clinical Immunology, Department of Medicine, University Hospital Münster, Münster, Germany; Department of Immunobiology, Yale University School of Medicine, New Haven, Connecticut, USA.
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67
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Tan Y, Tey HL, Chong SZ, Ng LG. Skin-ny deeping: Uncovering immune cell behavior and function through imaging techniques. Immunol Rev 2021; 306:271-292. [PMID: 34859448 DOI: 10.1111/imr.13049] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Accepted: 11/11/2021] [Indexed: 12/16/2022]
Abstract
As the largest organ of the body, the skin is a key barrier tissue with specialized structures where ongoing immune surveillance is critical for protecting the body from external insults. The innate immune system acts as first-responders in a coordinated manner to react to injury or infections, and recent developments in intravital imaging techniques have made it possible to delineate dynamic immune cell responses in a spatiotemporal manner. We review here key studies involved in understanding neutrophil, dendritic cell and macrophage behavior in skin and further discuss how this knowledge collectively highlights the importance of interactions and cellular functions in a systems biology manner. Furthermore, we will review emerging imaging technologies such as high-content proteomic screening, spatial transcriptomics and three-dimensional volumetric imaging and how these techniques can be integrated to provide a systems overview of the immune system that will further our current knowledge and lead to potential exciting discoveries in the upcoming decades.
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Affiliation(s)
- Yingrou Tan
- Singapore Immunology Network, Singapore, Singapore.,National Skin Centre, National Healthcare Group, Singapore, Singapore
| | - Hong Liang Tey
- National Skin Centre, National Healthcare Group, Singapore, Singapore.,Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.,Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore, Singapore
| | | | - Lai Guan Ng
- Singapore Immunology Network, Singapore, Singapore.,National Skin Centre, National Healthcare Group, Singapore, Singapore.,Department of Microbiology, Yong Loo Lin School of Medicine, National University of Singapore.,School of Biological Sciences, Nanyang Technological University, Singapore, Singapore
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68
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Dhariwala MO, Scharschmidt TC. Baby's skin bacteria: first impressions are long-lasting. Trends Immunol 2021; 42:1088-1099. [PMID: 34743922 DOI: 10.1016/j.it.2021.10.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 10/08/2021] [Accepted: 10/11/2021] [Indexed: 12/12/2022]
Abstract
Early life is a dynamic period for skin microbial colonization and immune development. We postulate that microbial exposures in this period durably alter the skin immune trajectory and later disease susceptibility. Bacteria contribute to infant skin immune imprinting via interactions with microbes as well as with cutaneous epithelial and immune cells. Excellent research is underway at the skin microbiome-immune interface, both in deciphering basic mechanisms and implementing their therapeutic applications. As emphasized herein, focusing on the unique opportunities and challenges presented by microbial immune modulation in early life will be important. In our view, only through dedicated study of skin-microbe crosstalk in this developmental window can we elucidate the molecular underpinnings of pivotal events that contribute to sustained host-microbe symbiosis.
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Affiliation(s)
- Miqdad O Dhariwala
- Department of Dermatology, University of California San Francisco (UCSF), San Francisco, CA 94143, USA
| | - Tiffany C Scharschmidt
- Department of Dermatology, University of California San Francisco (UCSF), San Francisco, CA 94143, USA.
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69
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Boothby IC, Kinet MJ, Boda DP, Kwan EY, Clancy S, Cohen JN, Habrylo I, Lowe MM, Pauli M, Yates AE, Chan JD, Harris HW, Neuhaus IM, McCalmont TH, Molofsky AB, Rosenblum MD. Early-life inflammation primes a T helper 2 cell-fibroblast niche in skin. Nature 2021; 599:667-672. [PMID: 34707292 PMCID: PMC8906225 DOI: 10.1038/s41586-021-04044-7] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Accepted: 09/20/2021] [Indexed: 12/18/2022]
Abstract
Inflammation early in life can prime the local immune milieu of peripheral tissues, which can cause lasting changes in immunological tone that confer disease protection or susceptibility1. The cellular and molecular mechanisms that prompt changes in immune tone in many nonlymphoid tissues remain largely unknown. Here we find that time-limited neonatal inflammation induced by a transient reduction in neonatal regulatory T cells causes a dysregulation of subcutaneous tissue in mouse skin. This is accompanied by the selective accumulation of type 2 helper T (TH2) cells within a distinct microanatomical niche. TH2 cells are maintained into adulthood through interactions with a fibroblast population in skin fascia that we refer to as TH2-interacting fascial fibroblasts (TIFFs), which expand in response to TH2 cytokines to form subcutaneous fibrous bands. Activation of the TH2-TIFF niche due to neonatal inflammation primes the skin for altered reparative responses to wounding. Furthermore, we identify fibroblasts in healthy human skin that express the TIFF transcriptional signature and detect these cells at high levels in eosinophilic fasciitis, an orphan disease characterized by inflammation and fibrosis of the skin fascia. Taken together, these data define a previously unidentified TH2 cell niche in skin and functionally characterize a disease-associated fibroblast population. The results also suggest a mechanism of immunological priming whereby inflammation early in life creates networks between adaptive immune cells and stromal cells to establish an immunological set-point in tissues that is maintained throughout life.
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Affiliation(s)
- Ian C. Boothby
- Department of Dermatology, University of California at San Franscisco, San Francisco, CA, USA.,Medical Scientist Training Program, University of California at San Franscisco, San Francisco, CA, USA
| | - Maxime J. Kinet
- Division of Rheumatology, Department of Medicine, University of California at San Franscisco, San Francisco, CA, USA
| | - Devi P. Boda
- Department of Dermatology, University of California at San Franscisco, San Francisco, CA, USA
| | - Elaine Y. Kwan
- Department of Dermatology, University of California at San Franscisco, San Francisco, CA, USA.,California Institute of Regenerative Medicine, San Francisco State University, San Francisco, CA, USA
| | - Sean Clancy
- Department of Dermatology, University of California at San Franscisco, San Francisco, CA, USA
| | - Jarish N. Cohen
- Department of Pathology, University of California at San Franscisco, San Francisco, CA, USA
| | - Ireneusz Habrylo
- Department of Dermatology, University of California at San Franscisco, San Francisco, CA, USA.,Medical Scientist Training Program, University of California at San Franscisco, San Francisco, CA, USA
| | - Margaret M. Lowe
- Department of Dermatology, University of California at San Franscisco, San Francisco, CA, USA
| | - Mariela Pauli
- Department of Dermatology, University of California at San Franscisco, San Francisco, CA, USA
| | - Ashley E. Yates
- Department of Dermatology, University of California at San Franscisco, San Francisco, CA, USA
| | - Jamie D. Chan
- Department of Pathology, University of California at San Franscisco, San Francisco, CA, USA
| | - Hobart W. Harris
- Department of Surgery, University of California at San Franscisco, San Francisco, CA, USA
| | - Isaac M. Neuhaus
- Department of Dermatology, University of California at San Franscisco, San Francisco, CA, USA
| | - Timothy H. McCalmont
- Department of Dermatology, University of California at San Franscisco, San Francisco, CA, USA.,Department of Pathology, University of California at San Franscisco, San Francisco, CA, USA
| | - Ari B. Molofsky
- Department of Laboratory Medicine, University of California at San Franscisco, San Francisco, CA, USA
| | - Michael D. Rosenblum
- Department of Dermatology, University of California at San Franscisco, San Francisco, CA, USA.,Correspondence and requests for materials should be addressed to Michael D. Rosenblum.
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70
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Sjaastad LE, Owen DL, Tracy SI, Farrar MA. Phenotypic and Functional Diversity in Regulatory T Cells. Front Cell Dev Biol 2021; 9:715901. [PMID: 34631704 PMCID: PMC8495164 DOI: 10.3389/fcell.2021.715901] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2021] [Accepted: 09/03/2021] [Indexed: 12/14/2022] Open
Abstract
The concept that a subset of T cells exists that specifically suppresses immune responses was originally proposed over 50 years ago. It then took the next 30 years to solidify the concept of regulatory T cells (Tregs) into the paradigm we understand today – namely a subset of CD4+ FOXP3+ T-cells that are critical for controlling immune responses to self and commensal or environmental antigens that also play key roles in promoting tissue homeostasis and repair. Expression of the transcription factor FOXP3 is a defining feature of Tregs, while the cytokine IL2 is necessary for robust Treg development and function. While our initial conception of Tregs was as a monomorphic lineage required to suppress all types of immune responses, recent work has demonstrated extensive phenotypic and functional diversity within the Treg population. In this review we address the ontogeny, phenotype, and function of the large number of distinct effector Treg subsets that have been defined over the last 15 years.
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Affiliation(s)
- Louisa E Sjaastad
- Department of Laboratory Medicine and Pathology, Center for Immunology, Masonic Cancer Center, University of Minnesota, Minneapolis, MN, United States
| | - David L Owen
- Department of Laboratory Medicine and Pathology, Center for Immunology, Masonic Cancer Center, University of Minnesota, Minneapolis, MN, United States
| | - Sean I Tracy
- Department of Laboratory Medicine and Pathology, Center for Immunology, Masonic Cancer Center, University of Minnesota, Minneapolis, MN, United States.,Division of Hematology, Oncology and Transplantation, Department of Medicine, University of Minnesota, Minneapolis, MN, United States
| | - Michael A Farrar
- Department of Laboratory Medicine and Pathology, Center for Immunology, Masonic Cancer Center, University of Minnesota, Minneapolis, MN, United States
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71
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Novak N, Tordesillas L, Cabanillas B. Diversity of T cells in the skin: Novel insights. Int Rev Immunol 2021; 42:185-198. [PMID: 34607528 DOI: 10.1080/08830185.2021.1985116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
T cells populate the skin to provide an effective immunosurveillance against external insults and to maintain tissue homeostasis. Most cutaneous T cells are αβ T cells, however, γδ T cells also exist although in much lower frequency. Different subsets of αβ T cells can be found in the skin, such as short-lived effector T cells, central memory T cells, effector memory T cells, and tissue-resident memory T cells. Their differential biology, function, and location provide an ample spectrum of immune responses in the skin. Foxp3+ memory regulatory T cells have a pivotal role in maintaining homeostasis in the skin and their dysregulation has been linked with different skin pathologies. The skin also contains populations of non-classical T cells, such as γδ T cells, NK T cells, and MR1-restricted T cells. Their role in skin homeostasis and response to pathogens has been well established in the past years, however, there is also growing evidence of their role in mediating allergic skin inflammation and promoting sensitization to allergens. In this review, we provide an updated overview on the different subsets of T cells that populate the skin with a specific focus on their role in allergic skin inflammation.
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Affiliation(s)
- Natalija Novak
- Department of Dermatology and Allergy, University Hospital, Bonn, Germany
| | - Leticia Tordesillas
- Department of Tumor Biology, H. Lee Moffitt Cancer Center and Research Institute, Tampa, FL, USA
| | - Beatriz Cabanillas
- Department of Allergy, Research Institute Hospital 12 de Octubre, Madrid, Spain
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72
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Tan CY, Ramirez ZE, Surana NK. A Modern-World View of Host-Microbiota-Pathogen Interactions. THE JOURNAL OF IMMUNOLOGY 2021; 207:1710-1718. [PMID: 34544813 DOI: 10.4049/jimmunol.2100215] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 05/14/2021] [Indexed: 12/14/2022]
Abstract
The microbiota-the diverse set of commensal microbes that normally colonize humans-represents the first line of defense against infectious diseases. In this review, we summarize the direct and indirect mechanisms by which the microbiota modulates susceptibility to, and severity of, infections, with a focus on immunological mechanisms. Moreover, we highlight some of the ways that modern-world lifestyles have influenced the structure-function relationship between the microbiota and infectious diseases. Ultimately, understanding how the microbiota influences infectious risks will facilitate development of microbiota-derived therapeutics that bolster host defenses.
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Affiliation(s)
- Chin Yee Tan
- Division of Infectious Diseases, Department of Pediatrics, Duke University School of Medicine, Durham, NC.,Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC; and
| | - Zeni E Ramirez
- Division of Infectious Diseases, Department of Pediatrics, Duke University School of Medicine, Durham, NC.,Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC; and
| | - Neeraj K Surana
- Division of Infectious Diseases, Department of Pediatrics, Duke University School of Medicine, Durham, NC; .,Department of Molecular Genetics and Microbiology, Duke University School of Medicine, Durham, NC; and.,Department of Immunology, Duke University School of Medicine, Durham, NC
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73
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Lunjani N, Ahearn-Ford S, Dube FS, Hlela C, O'Mahony L. Mechanisms of microbe-immune system dialogue within the skin. Genes Immun 2021; 22:276-288. [PMID: 33993202 PMCID: PMC8497273 DOI: 10.1038/s41435-021-00133-9] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2021] [Revised: 04/09/2021] [Accepted: 04/26/2021] [Indexed: 02/01/2023]
Abstract
The prevalence and severity of dermatological conditions such as atopic dermatitis have increased dramatically during recent decades. Many of the factors associated with an altered risk of developing inflammatory skin disorders have also been shown to alter the composition and diversity of non-pathogenic microbial communities that inhabit the human host. While the most densely microbial populated organ is the gut, culture and non-culture-based technologies have revealed a dynamic community of bacteria, fungi, viruses and mites that exist on healthy human skin, which change during disease. In this review, we highlight some of the recent findings on the mechanisms through which microbes interact with each other on the skin and the signalling systems that mediate communication between the immune system and skin-associated microbes. In addition, we summarize the ongoing clinical studies that are targeting the microbiome in patients with skin disorders. While significant efforts are still required to decipher the mechanisms underpinning host-microbe communication relevant to skin health, it is likely that disease-related microbial communities, or Dermatypes, will help identify personalized treatments and appropriate microbial reconstitution strategies.
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Affiliation(s)
- Nonhlanhla Lunjani
- Department of Dermatology, University of Cape Town, Cape Town, South Africa
- APC Microbiome Ireland, University College Cork, Cork, Ireland
| | | | - Felix S Dube
- Department of Molecular and Cell Biology, Faculty of Science, University of Cape Town, Cape Town, South Africa
- Institute of Infectious Disease & Molecular Medicine, University of Cape Town, Cape Town, South Africa
| | - Carol Hlela
- Department of Dermatology, University of Cape Town, Cape Town, South Africa
| | - Liam O'Mahony
- APC Microbiome Ireland, University College Cork, Cork, Ireland.
- Department of Medicine, University College Cork, Cork, Ireland.
- School of Microbiology, University College Cork, Cork, Ireland.
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74
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Early development of the skin microbiome: therapeutic opportunities. Pediatr Res 2021; 90:731-737. [PMID: 32919387 PMCID: PMC7952468 DOI: 10.1038/s41390-020-01146-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 07/23/2020] [Accepted: 08/16/2020] [Indexed: 02/06/2023]
Abstract
As human skin hosts a diverse microbiota in health and disease, there is an emerging consensus that dysregulated interactions between host and microbiome may contribute to chronic inflammatory disease of the skin. Neonatal skin is a unique habitat, structurally similar to the adult but with a different profile of metabolic substrates, environmental stressors, and immune activity. The surface is colonized within moments of birth with a bias toward maternal strains. Initial colonists are outcompeted as environmental exposures increase and host skin matures. Nonetheless, early life microbial acquisitions may have long-lasting effects on health through modulation of host immunity and competitive interactions between bacteria. Microbial ecology and its influence on health have been of interest to dermatologists for >50 years, and an explosion of recent interest in the microbiome has prompted ongoing investigations of several microbial therapeutics for dermatological disease. In this review, we consider how recent insight into the host and microbial factors driving development of the skin microbiome in early life offers new opportunities for therapeutic intervention. IMPACT: Advancement in understanding molecular mechanisms of bacterial competition opens new avenues of investigation into dermatological disease. Primary development of the skin microbiome is determined by immunological features of the cutaneous habitat. Understanding coordinated microbial and immunological development in the pediatric patient requires a multidisciplinary synthesis of primary literature.
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75
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Suzuki T, Ito T, Gilhar A, Tokura Y, Reich K, Paus R. The hair follicle-psoriasis axis: Shared regulatory mechanisms and therapeutic targets. Exp Dermatol 2021; 31:266-279. [PMID: 34587317 DOI: 10.1111/exd.14462] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 09/09/2021] [Accepted: 09/24/2021] [Indexed: 12/17/2022]
Abstract
It has long been known that there is a special affinity of psoriasis for the scalp: Here, it occurs most frequently, lesions terminate sharply in frontal skin beyond the hair line and are difficult to treat. Yet, surprisingly, scalp psoriasis only rarely causes alopecia, even though the pilosebaceous unit clearly is affected. Here, we systematically explore the peculiar, insufficiently investigated connection between psoriasis and growing (anagen) terminal scalp hair follicles (HFs), with emphasis on shared regulatory mechanism and therapeutic targets. Interestingly, several drugs and stressors that can trigger/aggravate psoriasis can inhibit hair growth (e.g. beta-blockers, chloroquine, carbamazepine, interferon-alpha, perceived stress). Instead, several anti-psoriatic agents can stimulate hair growth (e.g. cyclosporine, glucocorticoids, dithranol, UV irradiation), while skin/HF trauma (Köbner phenomenon/depilation) favours the development of psoriatic lesions and induces anagen in "quiescent" (telogen) HFs. On this basis, we propose two interconnected working models: (a) the existence of a bidirectional "hair follicle-psoriasis axis," along which keratinocytes of anagen scalp HFs secrete signals that favour the development and maintenance of psoriatic scalp lesions and respond to signals from these lesions, and (b) that anagen induction and psoriatic lesions share molecular "switch-on" mechanisms, which invite pharmacological targeting, once identified. Therefore, we advocate a novel, cross-fertilizing and integrative approach to psoriasis and hair research that systematically characterizes the "HF-psoriasis axis," focused on identification and therapeutic targeting of selected, shared signalling pathways in the future management of both, psoriasis and hair growth disorders.
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Affiliation(s)
- Takahiro Suzuki
- Dr. Phillip Frost Department of Dermatology & Cutaneous Surgery, University of Miami Miller School of Medicine, Miami, Florida, USA
| | - Taisuke Ito
- Department of Dermatology, Hamamatsu University School of Medicine, Hamamatsu, Japan
| | - Amos Gilhar
- Skin Research Laboratory, Rappaport Faculty of Medicine, Technion-Israel Institute of Technology, Haifa, Israel
| | - Yoshiki Tokura
- Department of Dermatology, Hamamatsu University School of Medicine, Hamamatsu, Japan.,Allergic Disease Research Center, Chutoen General Medical Center, Kakegawa, Japan
| | - Kristian Reich
- Institute for Health Services Research in Dermatology and Nursing, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.,Monasterium Laboratory, Münster, Germany
| | - Ralf Paus
- Dr. Phillip Frost Department of Dermatology & Cutaneous Surgery, University of Miami Miller School of Medicine, Miami, Florida, USA.,Monasterium Laboratory, Münster, Germany.,Centre for Dermatology Research, University of Manchester, Manchester, UK.,NIHR Manchester Biomedical Research Center, Manchester, UK
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76
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Mechanisms for control of skin immune function by the microbiome. Curr Opin Immunol 2021; 72:324-330. [PMID: 34537476 DOI: 10.1016/j.coi.2021.09.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Accepted: 09/07/2021] [Indexed: 11/22/2022]
Abstract
The skin represents the largest area for direct contact between microbes and host immunocytes and is a site for constant communication between the host and this diverse and essential microbial community. Coagulase-negative staphylococci are an abundant bacterial genus on the human skin and are regulated through various mechanisms that include the epidermal barrier environment and innate and adaptive immune systems within the epidermis and dermis. In turn, some species and strains of these bacteria produce beneficial products that augment host immunity by exerting specifically targeted antimicrobial, anti-inflammatory, or anti-neoplastic activity while also promoting broad innate and adaptive immune responses. The use of selected skin commensals as a therapeutic has shown promise in recent human clinical trials. This emerging concept of bacteriotherapy is defining mechanisms of action and validating the dependence on the microbiome for maintenance of immune homeostasis.
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77
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Maguire G. Stem cells part of the innate and adaptive immune systems as a therapeutic for Covid-19. Commun Integr Biol 2021; 14:186-198. [PMID: 34527167 PMCID: PMC8437473 DOI: 10.1080/19420889.2021.1965356] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 07/29/2021] [Accepted: 08/03/2021] [Indexed: 12/17/2022] Open
Abstract
Some stem cell types not only release molecules that reduce viral replication, but also reduce the hypercytokinemia and inflammation induced by the immune system, and have been found to be part of the innate and adaptive immune systems. An important component of the stem cell's ability to ameliorate viral diseases, especially the complications post-clearance of the pathogen, is the ability of adult stem cells to reset the innate and adaptive immune systems from an inflammatory state to a repair state. Thus, the molecules released from certain stem cell types found to be safe and efficacious, may be an important new means for therapeutic development in Covid-19, especially for late-stage inflammation and tissue damage once the virus has cleared, particularly in the aged population.
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Affiliation(s)
- Greg Maguire
- Dept. of Preventative and Medicinal Chemistry, NeoGenesis Inc. And BioRegenerative Sciences Inc, San Diego, CA, USA
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78
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Shao Q, Gu J, Zhou J, Wang Q, Li X, Deng Z, Lu L. Tissue Tregs and Maintenance of Tissue Homeostasis. Front Cell Dev Biol 2021; 9:717903. [PMID: 34490267 PMCID: PMC8418123 DOI: 10.3389/fcell.2021.717903] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Accepted: 07/28/2021] [Indexed: 12/21/2022] Open
Abstract
Regulatory T cells (Tregs) specifically expressing Forkhead box P3 (Foxp3) play roles in suppressing the immune response and maintaining immune homeostasis. After maturation in the thymus, Tregs leave the thymus and migrate to lymphoid tissues or non-lymphoid tissues. Increasing evidence indicates that Tregs with unique characteristics also have significant effects on non-lymphoid peripheral tissues. Tissue-resident Tregs, also called tissue Tregs, do not recirculate in the blood or lymphatics and attain a unique phenotype distinct from common Tregs in circulation. This review first summarizes the phenotype, function, and cytokine expression of these Tregs in visceral adipose tissue, skin, muscle, and other tissues. Then, how Tregs are generated, home, and are attracted to and remain resident in the tissue are discussed. Finally, how an increased understanding of these tissue Tregs might guide clinical treatment is discussed.
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Affiliation(s)
- Qing Shao
- Hepatobiliary Center, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China.,Research Unit of Liver Transplantation and Transplant Immunology, Chinese Academy of Medical Sciences, Nanjing, China.,Jiangsu Cancer Hospital, Jiangsu Institute of Cancer Research, Nanjing Medical University Affiliated Cancer Hospital, Nanjing, China.,Jiangsu Key Laboratory of Cancer Biomarkers, Prevention and Treatment, Collaborative Innovation Center for Cancer Personalized Medicine, Nanjing Medical University, Nanjing, China
| | - Jian Gu
- Hepatobiliary Center, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China.,Research Unit of Liver Transplantation and Transplant Immunology, Chinese Academy of Medical Sciences, Nanjing, China.,Jiangsu Cancer Hospital, Jiangsu Institute of Cancer Research, Nanjing Medical University Affiliated Cancer Hospital, Nanjing, China.,Jiangsu Key Laboratory of Cancer Biomarkers, Prevention and Treatment, Collaborative Innovation Center for Cancer Personalized Medicine, Nanjing Medical University, Nanjing, China
| | - Jinren Zhou
- Hepatobiliary Center, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China.,Research Unit of Liver Transplantation and Transplant Immunology, Chinese Academy of Medical Sciences, Nanjing, China.,Jiangsu Cancer Hospital, Jiangsu Institute of Cancer Research, Nanjing Medical University Affiliated Cancer Hospital, Nanjing, China.,Jiangsu Key Laboratory of Cancer Biomarkers, Prevention and Treatment, Collaborative Innovation Center for Cancer Personalized Medicine, Nanjing Medical University, Nanjing, China
| | - Qi Wang
- Hepatobiliary Center, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China.,Research Unit of Liver Transplantation and Transplant Immunology, Chinese Academy of Medical Sciences, Nanjing, China.,Jiangsu Cancer Hospital, Jiangsu Institute of Cancer Research, Nanjing Medical University Affiliated Cancer Hospital, Nanjing, China.,Jiangsu Key Laboratory of Cancer Biomarkers, Prevention and Treatment, Collaborative Innovation Center for Cancer Personalized Medicine, Nanjing Medical University, Nanjing, China
| | - Xiangyu Li
- Hepatobiliary Center, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China.,Research Unit of Liver Transplantation and Transplant Immunology, Chinese Academy of Medical Sciences, Nanjing, China.,Jiangsu Cancer Hospital, Jiangsu Institute of Cancer Research, Nanjing Medical University Affiliated Cancer Hospital, Nanjing, China.,Jiangsu Key Laboratory of Cancer Biomarkers, Prevention and Treatment, Collaborative Innovation Center for Cancer Personalized Medicine, Nanjing Medical University, Nanjing, China
| | - Zhenhua Deng
- Hepatobiliary Center, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China.,Research Unit of Liver Transplantation and Transplant Immunology, Chinese Academy of Medical Sciences, Nanjing, China.,Jiangsu Cancer Hospital, Jiangsu Institute of Cancer Research, Nanjing Medical University Affiliated Cancer Hospital, Nanjing, China.,Jiangsu Key Laboratory of Cancer Biomarkers, Prevention and Treatment, Collaborative Innovation Center for Cancer Personalized Medicine, Nanjing Medical University, Nanjing, China
| | - Ling Lu
- Hepatobiliary Center, The First Affiliated Hospital of Nanjing Medical University, Nanjing, China.,Research Unit of Liver Transplantation and Transplant Immunology, Chinese Academy of Medical Sciences, Nanjing, China.,Jiangsu Cancer Hospital, Jiangsu Institute of Cancer Research, Nanjing Medical University Affiliated Cancer Hospital, Nanjing, China.,Jiangsu Key Laboratory of Cancer Biomarkers, Prevention and Treatment, Collaborative Innovation Center for Cancer Personalized Medicine, Nanjing Medical University, Nanjing, China
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79
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Abstract
The FOXP3+CD4+ regulatory T (Treg) cells located in non-lymphoid tissues differ in phenotype and function from their lymphoid organ counterparts. Tissue Treg cells have distinct transcriptomes, T cell receptor repertoires and growth and survival factor dependencies that arm them to survive and operate in their home tissue. Their functions extend beyond immune surveillance to tissue homeostasis, including regulation of local and systemic metabolism, promotion of tissue repair and regeneration, and control of the proliferation, differentiation and fate of non-lymphoid cell progenitors. Treg cells in diverse tissues share a common FOXP3+CD4+ precursor located within lymphoid organs. This precursor undergoes definitive specialization once in the home tissue, following a multilayered array of common and tissue-distinct transcriptional programmes. Our deepening knowledge of tissue Treg cell biology will inform ongoing attempts to harness Treg cells for precision immunotherapeutics.
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80
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Abstract
Careful attention to detail and adherence to procedure guidelines when inserting and managing intravascular catheters has decreased the incidence of catheter-related bloodstream infections (CRBSIs). In order to limit these, health professionals must understand the underlying microbiology. Biofilms can explain the clinical findings most often seen with CRBSIs, yet they are poorly understood within medicine. Bacteria growing on solid surfaces such as a catheter are predominantly in biofilm phenotype, with a group of genes active that allow the bacteria to be tolerant to antiseptics and antibiotics by producing a self-secreted protective matrix. It is unclear whether it is planktonic seeding or small fragments of biofilm breaking off into the bloodstream that eventually results in the acute infection. The literature identifies four routes for microbes to adhere to a catheter and start biofilm formation: catheter contact, catheter insertion, catheter management and non-catheter-related sources. Routine clinical culture methods are inadequate to fully identify microbes producing catheter biofilm and/or bloodstream infection, therefore DNA methods may be required to diagnose CRBSIs. Treatment is removal and reinsertion of the catheter in a different site when possible. However, antibiofilm strategies can be employed to try to salvage the catheter. The use of high-dose antiseptics or antibiotics for long durations inside the catheter and hub (antibiotic/antiseptic lock) can suppress biofilm enough to reduce the seeding of the blood below a level where the patient's immune system can prevent bloodstream infection.
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Affiliation(s)
- Randy Wolcott
- Physician, Southwest Regional Wound Care Center, Lubbock, Texas, USA
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81
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Runge S, Rosshart SP. The Mammalian Metaorganism: A Holistic View on How Microbes of All Kingdoms and Niches Shape Local and Systemic Immunity. Front Immunol 2021; 12:702378. [PMID: 34276696 PMCID: PMC8278200 DOI: 10.3389/fimmu.2021.702378] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Accepted: 06/17/2021] [Indexed: 12/12/2022] Open
Abstract
The field of microbiome research has developed rapidly over the past decades and has become a topic of major interest to basic, preclinical, and clinical research, the pharmaceutical industry as well as the general public. The microbiome is a complex and diverse ecosystem and defined as the collection of all host-associated microorganisms and their genes. It is acquired through vertical transmission and environmental exposure and includes microbes of all kingdoms: bacteria, archaea, prokaryotic and eukaryotic viruses, fungi, protozoa, and the meiofauna. These microorganisms co-evolved with their respective hosts over millions of years, thereby establishing a mutually beneficial, symbiotic relationship on all epithelial barriers. Thus, the microbiome plays a pivotal role in virtually every aspect of mammalian physiology, particularly in the development, homeostasis, and function of the immune system. Consequently, the combination of the host genome and the microbial genome, together referred to as the metagenome, largely drives the mammalian phenotype. So far, the majority of studies have unilaterally focused on the gastrointestinal bacterial microbiota. However, recent work illustrating the impact of viruses, fungi, and protozoa on host immunity urges us towards a holistic view of the mammalian microbiome and the appreciation for its non-bacterial kingdoms. In addition, the importance of microbiota on epithelial barriers other than the gut as well as their systemic effects via microbially-derived biologically active compounds is increasingly recognized. Here, we want to provide a brief but comprehensive overview of the most important findings and the current knowledge on how microbes of all kingdoms and microbial niches shape local and systemic immunity in health and disease.
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Affiliation(s)
- Solveig Runge
- Department of Medicine II (Gastroenterology, Hepatology, Endocrinology, and Infectious Diseases), Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg im Breisgau, Germany.,Faculty of Biology, University of Freiburg, Freiburg im Breisgau, Germany
| | - Stephan Patrick Rosshart
- Department of Medicine II (Gastroenterology, Hepatology, Endocrinology, and Infectious Diseases), Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Freiburg im Breisgau, Germany
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82
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Noel JC, Berin MC. Role of innate immunity and myeloid cells in susceptibility to allergic disease. Ann N Y Acad Sci 2021; 1499:42-53. [PMID: 34159612 DOI: 10.1111/nyas.14654] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 06/04/2021] [Accepted: 06/08/2021] [Indexed: 12/15/2022]
Abstract
Allergic diseases, including asthma, food allergy, eczema, and allergic rhinitis, are common diseases increasing in prevalence. Allergy, a failure of immune tolerance to innocuous environmental allergens, is characterized by allergen-specific immune responses, including IgE antibodies and T helper and T follicular helper cells producing type 2 cytokines. Despite the central role of adaptive immunity in pathophysiology of allergy, there is a growing body of evidence indicating an important role for the innate immune system in allergic disease. In this review, we focus on epithelial-mononuclear phagocyte communication in the control of allergy and tolerance. We discuss studies on early life environmental exposures and allergy susceptibility, and the evidence for innate training of mononuclear phagocytes as the mechanistic link between exposure and health or disease.
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Affiliation(s)
- Justine C Noel
- Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, New York
| | - M Cecilia Berin
- Precision Immunology Institute, Icahn School of Medicine at Mount Sinai, New York, New York
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83
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Contact Dermatitis Associated With Hair Care Products: A Retrospective Analysis of the North American Contact Dermatitis Group Data, 2001-2016. Dermatitis 2021; 33:91-102. [PMID: 34149001 DOI: 10.1097/der.0000000000000760] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND Hair care products (HCPs) may cause both allergic contact dermatitis (ACD) and irritant contact dermatitis (ICD). OBJECTIVES The aims of the study were to determine the prevalence of HCP-associated ICD/ACD and to characterize relevant allergens. METHODS This study is a retrospective analysis of North American Contact Dermatitis Group (NACDG) patch test data, 2001-2016. RESULTS Of 38,775 patients tested, 3481 (9.0%) had positive patch test reactions associated with HCPs. The HCP-positive patients were significantly more likely to be female (79.9% vs 66.0%) and/or have primary sites of dermatitis on the face (32.0% vs 27.8%) or scalp (15.4% vs 2.2%) compared with the HCP-negative patients (P < 0.0001). Of 4908 HCP-associated positive patch test reactions, 86.9% (n = 4263) were due to allergens on the NACDG screening series; p-phenylenediamine (35.8%), methylisothiazolinone (9.7%), methylchloroisothiazolinone/methylisothiazolinone (8.7%), and cocamidopropyl betaine (5.9%) were the most frequent. Most reactions (87.7%, 3736/4263) were currently clinically relevant. The most common job associated with 366 occupationally related NACDG HCP-associated allergens was hairdresser/cosmetologist (71.9%). Two hundred eighty-two patients (0.7%) had ICD associated with HCPs. Shampoo/conditioners were the most frequent source of NACDG HCP-associated reactions (47.3%) and HCP-associated ICD (45.0%). CONCLUSIONS Of the HCP-positive patients, 18.5% had HCP reactions to allergens not on the NACDG screening series, underscoring the importance of patch testing to expanded series in patients suspected of HCP allergy.
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84
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Nakatsuji T, Gallo RL, Shafiq F, Tong Y, Chun K, Butcher AM, Cheng JY, Hata TR. Use of Autologous Bacteriotherapy to Treat Staphylococcus aureus in Patients With Atopic Dermatitis: A Randomized Double-blind Clinical Trial. JAMA Dermatol 2021; 157:2781297. [PMID: 34132739 PMCID: PMC8209585 DOI: 10.1001/jamadermatol.2021.1311] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Accepted: 04/21/2021] [Indexed: 12/30/2022]
Abstract
IMPORTANCE Atopic dermatitis (AD) can be negatively affected by Staphylococcus aureus. The skin microbiome of AD is deficient in coagulase-negative Staphylococcus (CoNS) that can kill S aureus. OBJECTIVE To evaluate if the antimicrobial-producing CoNS (CoNS-AM+) of a patient with AD can be autologously reintroduced to the same patient to inhibit survival of S aureus and improve clinical outcomes. DESIGN, SETTING, AND PARTICIPANTS This double-blind, vehicle-controlled, single-center randomized clinical trial of 11 adult patients with moderate to severe AD who were randomized to receive either an autologous CoNS-AM+ (n = 5) or the vehicle (n = 6) was conducted between April 2016 and May 2018. The data were analyzed from May 2018 to July 2019. INTERVENTIONS Autologous CoNS-AM+ was isolated from swabs that were obtained from the nonlesional skin of each patient with AD, expanded by culture, and then reapplied topically to the forearms at a concentration of 107 colony-forming units/g. MAIN OUTCOMES AND MEASURES The primary end point of this study was to assess S aureus abundance after 1 week of application of autologous CoNS-AM+ on patients with AD by culture-based and DNA-based methods. The secondary end points were to assess the safety and clinical outcomes. RESULTS Eleven patients (4 men [36.4%] and 7 women [63/6%]) were recruited based on the inclusion criteria. There were no serious adverse events in groups treated with autologous CoNS-AM+ or the vehicle. Staphylococcus aureus colonization on lesional skin at the end of treatment on patients who were treated with autologous CoNS-AM+ (mean of log10 ratio to baseline, -1.702; 95% CI, -2.882 to -0.523) was reduced by 99.2% compared with vehicle treatment (mean of log10 ratio to baseline, 0.671; 95% CI, -0.289 to 1.613; P = .01) and persisted for 4 days after treatment (CoNS-AM+: mean of log10 ratio to baseline, -1.752; 95% CI, -3.051 to -0.453; vehicle: mean of log10 ratio to baseline, -0.003; 95% CI, -1.083 to 1.076; P = .03). Importantly, local Eczema Area And Severity Index scores that were assessed at day 11 on patients who received CoNS-AM+ (mean of percentage change, -48.45; 95% CI, -84.34 to -12.55) were significantly improved compared with vehicle treatment (mean of percentage change, -4.52; 95% CI, -36.25 to 27.22; P = .04). CONCLUSIONS AND RELEVANCE The data from this randomized clinical trial suggest that bacteriotherapy with an autologous strain of skin commensal bacteria can safely decrease S aureus colonization and improve disease severity. Although larger studies will be needed, this personalized approach for S aureus reduction may provide an alternative treatment for patients with AD beyond antibiotics, immunosuppression, and immunomodulation. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT03158012.
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Affiliation(s)
- Teruaki Nakatsuji
- Department of Dermatology, University of California, San Diego, La Jolla
| | - Richard L. Gallo
- Department of Dermatology, University of California, San Diego, La Jolla
| | - Faiza Shafiq
- Department of Dermatology, University of California, San Diego, La Jolla
| | - Yun Tong
- Department of Dermatology, University of California, San Diego, La Jolla
| | - Kimberly Chun
- Department of Dermatology, University of California, San Diego, La Jolla
| | - Anna M. Butcher
- Department of Dermatology, University of California, San Diego, La Jolla
| | - Joyce Y. Cheng
- Department of Dermatology, University of California, San Diego, La Jolla
| | - Tissa R. Hata
- Department of Dermatology, University of California, San Diego, La Jolla
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85
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Adade EE, Al Lakhen K, Lemus AA, Valm AM. Recent progress in analyzing the spatial structure of the human microbiome: distinguishing biogeography and architecture in the oral and gut communities. CURRENT OPINION IN ENDOCRINE AND METABOLIC RESEARCH 2021; 18:275-283. [PMID: 35936977 PMCID: PMC9351436 DOI: 10.1016/j.coemr.2021.04.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Fueled by technological advances in methods for sample collection and preservation in sequencing studies, and in advances in computational analyses of high content image data, the spatial structure of the human microbiome is coming to light. In this mini-review, we summarize recent developments in our understanding of the structure of two human microbiomes: the lower gut and the oral cavity. We focus on only the most recent literature and we make an important distinction between two forms of spatial structure, governed by scale: biogeography and architecture. By segmenting the study of microbiome spatial structure into two categories, we demonstrate the potential to greatly advance our understanding of the mechanistic principles that link structure and function in the microbiome.
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Affiliation(s)
- Emmanuel E. Adade
- Department of Biological Sciences, State University of New York at Albany, Albany, NY 12222 USA
| | - Khalid Al Lakhen
- Department of Biological Sciences, State University of New York at Albany, Albany, NY 12222 USA
| | - Alex A. Lemus
- Department of Biological Sciences, State University of New York at Albany, Albany, NY 12222 USA
| | - Alex M. Valm
- Department of Biological Sciences, State University of New York at Albany, Albany, NY 12222 USA,Corresponding author.
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86
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Niec RE, Rudensky AY, Fuchs E. Inflammatory adaptation in barrier tissues. Cell 2021; 184:3361-3375. [PMID: 34171319 DOI: 10.1016/j.cell.2021.05.036] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2021] [Revised: 04/27/2021] [Accepted: 05/19/2021] [Indexed: 02/08/2023]
Abstract
Surface epithelia provide a critical barrier to the outside world. Upon a barrier breach, resident epithelial and immune cells coordinate efforts to control infections and heal tissue damage. Inflammation can etch lasting marks within tissues, altering features such as scope and quality of future responses. By remembering inflammatory experiences, tissues are better equipped to quickly and robustly respond to barrier breaches. Alarmingly, in disease states, memory may fuel the inflammatory fire. Here, we review the cellular communication networks in barrier tissues and the integration between tissue-resident and recruited immune cells and tissue stem cells underlying tissue adaptation to environmental stress.
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Affiliation(s)
- Rachel E Niec
- Robin Chemers Neustein Laboratory of Mammalian Cell Biology and Development, Howard Hughes Medical Institute, The Rockefeller University, New York, NY 10065, USA; Department of Gastroenterology and Hepatology, Weill Cornell Medicine, Cornell University, New York, NY 10065, USA
| | - Alexander Y Rudensky
- Howard Hughes Medical Institute and Ludwig Center at Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA; Immunology Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA.
| | - Elaine Fuchs
- Robin Chemers Neustein Laboratory of Mammalian Cell Biology and Development, Howard Hughes Medical Institute, The Rockefeller University, New York, NY 10065, USA.
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87
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Abstract
The skin microbiome is an ecosystem comprised of a multitude of microbial species interacting with their surroundings, including other microbes and host epithelial and immune cells. These interactions are the basis of important roles within the skin microbiome that provide benefit to the host, boosting multiple aspects of barrier function, a critical function of this essential organ. However, with reward always comes risk; resident skin microbes function in a context-dependent manner, set on the backdrop of a dynamic host and microbial milieu. Here, we discuss the reward of hosting a microbial ecosystem on the skin, including protection from pathogens and tuning of the skin microenvironment. We also give consideration to how these skin residents, often termed "commensals" can cause disorder, damage, and promote skin disease.
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Affiliation(s)
- Laurice Flowers
- Department of Dermatology, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA, USA
| | - Elizabeth A Grice
- Department of Dermatology, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA, USA.
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88
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Bier K, Schittek B. Beneficial effects of coagulase-negative Staphylococci on Staphylococcus aureus skin colonization. Exp Dermatol 2021; 30:1442-1452. [PMID: 33960019 DOI: 10.1111/exd.14381] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 04/15/2021] [Accepted: 04/29/2021] [Indexed: 12/11/2022]
Abstract
Our skin is constantly exposed to a large number of pathogens while at the same time undergoing selective colonization by commensal microorganisms such as coagulase-negative Staphylococci. Staphylococcus aureus, however, is a facultative pathogen that is usually absent from healthy skin but frequently colonizes the inflamed skin of atopic dermatitis patients, where it further promotes inflammation. Enhanced S. aureus skin colonization was shown to correlate with a loss of microbiome diversity indicating a role for skin commensals to shape pathogen colonization. Together, keratinocytes and immune cells in the skin need to discriminate commensals from pathogens and orchestrate subsequent immune reactions in response to colonizing microbes. However, the mechanisms how individual commensals cooperate with keratinocytes and the immune system of the skin to prevent pathogen colonization are barely understood. In this review, we discuss the current knowledge on the functional effects of coagulase-negative staphylococci, the most frequently isolated skin commensals, on S. aureus skin colonization.
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Affiliation(s)
- Katharina Bier
- Division of Dermatooncology, Department of Dermatology, University of Tübingen, Tübingen, Germany
| | - Birgit Schittek
- Division of Dermatooncology, Department of Dermatology, University of Tübingen, Tübingen, Germany
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89
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Lousada MB, Lachnit T, Edelkamp J, Rouillé T, Ajdic D, Uchida Y, Di Nardo A, Bosch TCG, Paus R. Exploring the human hair follicle microbiome. Br J Dermatol 2021; 184:802-815. [PMID: 32762039 DOI: 10.1111/bjd.19461] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/31/2020] [Indexed: 12/31/2022]
Abstract
Human hair follicles (HFs) carry complex microbial communities that differ from the skin surface microbiota. This likely reflects that the HF epithelium differs from the epidermal barrier in that it provides a moist, less acidic, and relatively ultraviolet light-protected environment, part of which is immune-privileged, thus facilitating microbial survival. Here we review the current understanding of the human HF microbiome and its potential physiological and pathological functions, including in folliculitis, acne vulgaris, hidradenitis suppurativa, alopecia areata and cicatricial alopecias. While reviewing the main human HF bacteria (such as Propionibacteria, Corynebacteria, Staphylococci and Streptococci), viruses, fungi and parasites as human HF microbiome constituents, we advocate a broad view of the HF as an integral part of the human holobiont. Specifically, we explore how the human HF may manage its microbiome via the regulated production of antimicrobial peptides (such as cathelicidin, psoriasin, RNAse7 and dermcidin) by HF keratinocytes, how the microbiome may impact on cytokine and chemokine release from the HF, and examine hair growth-modulatory effects of antibiotics, and ask whether the microbiome affects hair growth in turn. We highlight major open questions and potential novel approaches to the management of hair diseases by targeting the HF microbiome.
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Affiliation(s)
- M B Lousada
- Monasterium Laboratory, Münster, Germany
- Zoological Institute, Christian-Albrechts University Kiel, Kiel, Germany
| | - T Lachnit
- Zoological Institute, Christian-Albrechts University Kiel, Kiel, Germany
| | - J Edelkamp
- Monasterium Laboratory, Münster, Germany
| | - T Rouillé
- Monasterium Laboratory, Münster, Germany
| | - D Ajdic
- Dr. Phillip Frost Department of Dermatology & Cutaneous Surgery, University of Miami Miller School of Medicine, Miami, FL, USA
| | - Y Uchida
- Monasterium Laboratory, Münster, Germany
| | - A Di Nardo
- Department of Dermatology, University of California, San Diego, CA, USA
| | - T C G Bosch
- Zoological Institute, Christian-Albrechts University Kiel, Kiel, Germany
| | - R Paus
- Monasterium Laboratory, Münster, Germany
- Dr. Phillip Frost Department of Dermatology & Cutaneous Surgery, University of Miami Miller School of Medicine, Miami, FL, USA
- Centre for Dermatology Research, School of Biological Sciences, University of Manchester & NIHR Biomedical Research Centre, Manchester, UK
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90
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Pirozzolo I, Li Z, Sepulveda M, Alegre ML. Influence of the microbiome on solid organ transplant survival. J Heart Lung Transplant 2021; 40:745-753. [PMID: 34030971 DOI: 10.1016/j.healun.2021.04.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 04/06/2021] [Accepted: 04/11/2021] [Indexed: 10/21/2022] Open
Abstract
The microbiome is an environmental factor in intricate symbiotic relationship with its hosts' immune system, potentially shaping anticancer immunity, autoimmunity, and transplant responses. The focus of this review is to discuss recent findings tying the microbiota to transplant outcomes and alloimmunity. The microbiota changes dynamically following transplantation, but whether these changes affect transplant outcomes can be difficult to parse out. New data reveal effects of the microbiota locally, as well as systemically, depending on the mucosal/epithelial surface colonized, the specific commensal communities present and the nature of microbial-derived molecules produced. These complex interactions result in the microbiota potentially impacting transplantation at different levels, including modulation of donor and/or recipient cells, alterations in the priming and/or effector phases of the alloimmune response, availability or metabolism of immunosuppressive drugs, transplant fate or post-transplant complications.
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Affiliation(s)
- Isabella Pirozzolo
- Section of Rheumatology, Department of Medicine, University of Chicago, Chicago, Illinois
| | - Zhipeng Li
- Section of Rheumatology, Department of Medicine, University of Chicago, Chicago, Illinois
| | - Martin Sepulveda
- Section of Rheumatology, Department of Medicine, University of Chicago, Chicago, Illinois
| | - Maria-Luisa Alegre
- Section of Rheumatology, Department of Medicine, University of Chicago, Chicago, Illinois.
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91
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Nakatsuji T, Hata TR, Tong Y, Cheng JY, Shafiq F, Butcher AM, Salem SS, Brinton SL, Rudman Spergel AK, Johnson K, Jepson B, Calatroni A, David G, Ramirez-Gama M, Taylor P, Leung DYM, Gallo RL. Development of a human skin commensal microbe for bacteriotherapy of atopic dermatitis and use in a phase 1 randomized clinical trial. Nat Med 2021; 27:700-709. [PMID: 33619370 PMCID: PMC8052297 DOI: 10.1038/s41591-021-01256-2] [Citation(s) in RCA: 119] [Impact Index Per Article: 39.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Accepted: 01/15/2021] [Indexed: 01/31/2023]
Abstract
Staphylococcus aureus colonizes patients with atopic dermatitis (AD) and exacerbates disease by promoting inflammation. The present study investigated the safety and mechanisms of action of Staphylococcus hominis A9 (ShA9), a bacterium isolated from healthy human skin, as a topical therapy for AD. ShA9 killed S. aureus on the skin of mice and inhibited expression of a toxin from S. aureus (psmα) that promotes inflammation. A first-in-human, phase 1, double-blinded, randomized 1-week trial of topical ShA9 or vehicle on the forearm skin of 54 adults with S. aureus-positive AD (NCT03151148) met its primary endpoint of safety, and participants receiving ShA9 had fewer adverse events associated with AD. Eczema severity was not significantly different when evaluated in all participants treated with ShA9 but a significant decrease in S. aureus and increased ShA9 DNA were seen and met secondary endpoints. Some S. aureus strains on participants were not directly killed by ShA9, but expression of mRNA for psmα was inhibited in all strains. Improvement in local eczema severity was suggested by post-hoc analysis of participants with S. aureus directly killed by ShA9. These observations demonstrate the safety and potential benefits of bacteriotherapy for AD.
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Affiliation(s)
- Teruaki Nakatsuji
- Department of Dermatology, University of California, San Diego, La Jolla, CA, USA
| | - Tissa R Hata
- Department of Dermatology, University of California, San Diego, La Jolla, CA, USA
| | - Yun Tong
- Department of Dermatology, University of California, San Diego, La Jolla, CA, USA
| | - Joyce Y Cheng
- Department of Dermatology, University of California, San Diego, La Jolla, CA, USA
| | - Faiza Shafiq
- Department of Dermatology, University of California, San Diego, La Jolla, CA, USA
| | - Anna M Butcher
- Department of Dermatology, University of California, San Diego, La Jolla, CA, USA
| | - Secilia S Salem
- Department of Dermatology, University of California, San Diego, La Jolla, CA, USA
| | - Samantha L Brinton
- Department of Dermatology, University of California, San Diego, La Jolla, CA, USA
| | - Amanda K Rudman Spergel
- Division of Allergy, Immunology and Transplantation, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Keli Johnson
- Rho Federal Systems Division, Inc., Durham, NC, USA
| | - Brett Jepson
- Rho Federal Systems Division, Inc., Durham, NC, USA
| | | | - Gloria David
- Rho Federal Systems Division, Inc., Durham, NC, USA
| | - Marco Ramirez-Gama
- Division of Allergy and Immunology, Department of Pediatrics, National Jewish Health, Denver, CO, USA
| | - Patricia Taylor
- Division of Allergy and Immunology, Department of Pediatrics, National Jewish Health, Denver, CO, USA
| | - Donald Y M Leung
- Division of Allergy and Immunology, Department of Pediatrics, National Jewish Health, Denver, CO, USA
| | - Richard L Gallo
- Department of Dermatology, University of California, San Diego, La Jolla, CA, USA.
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92
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Wang G, Sweren E, Liu H, Wier E, Alphonse MP, Chen R, Islam N, Li A, Xue Y, Chen J, Park S, Chen Y, Lee S, Wang Y, Wang S, Archer NK, Andrews W, Kane MA, Dare E, Reddy SK, Hu Z, Grice EA, Miller LS, Garza LA. Bacteria induce skin regeneration via IL-1β signaling. Cell Host Microbe 2021; 29:777-791.e6. [PMID: 33798492 PMCID: PMC8122070 DOI: 10.1016/j.chom.2021.03.003] [Citation(s) in RCA: 66] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 01/03/2021] [Accepted: 02/24/2021] [Indexed: 02/08/2023]
Abstract
Environmental factors that enhance regeneration are largely unknown. The immune system and microbiome are attributed roles in repairing and regenerating structure but their precise interplay is unclear. Here, we assessed the function of skin bacteria in wound healing and wound-induced hair follicle neogenesis (WIHN), a rare adult organogenesis model. WIHN levels and stem cell markers correlate with bacterial counts, being lowest in germ-free (GF), intermediate in conventional specific pathogen-free (SPF), and highest in wild-type mice, even those infected with pathogenic Staphylococcus aureus. Reducing skin microbiota via cage changes or topical antibiotics decreased WIHN. Inflammatory cytokine IL-1β and keratinocyte-dependent IL-1R-MyD88 signaling are necessary and sufficient for bacteria to promote regeneration. Finally, in a small trial, a topical broad-spectrum antibiotic also slowed skin wound healing in adult volunteers. These results demonstrate a role for IL-1β to control morphogenesis and support the need to reconsider routine applications of topical prophylactic antibiotics.
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Affiliation(s)
- Gaofeng Wang
- Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, MD 21210, USA; Department of Plastic and Aesthetic Surgery, Nanfang Hospital of Southern Medical University, Guangzhou, Guangdong Province 510515, China
| | - Evan Sweren
- Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, MD 21210, USA
| | - Haiyun Liu
- Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, MD 21210, USA
| | - Eric Wier
- Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, MD 21210, USA
| | - Martin P Alphonse
- Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, MD 21210, USA
| | - Ruosi Chen
- Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, MD 21210, USA; Department of Plastic and Aesthetic Surgery, Nanfang Hospital of Southern Medical University, Guangzhou, Guangdong Province 510515, China
| | - Nasif Islam
- Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, MD 21210, USA
| | - Ang Li
- Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, MD 21210, USA
| | - Yingchao Xue
- Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, MD 21210, USA
| | - Junjie Chen
- Department of Mechanical Engineering, Johns Hopkins University, Baltimore, MD 21210, USA
| | - Seungman Park
- Department of Mechanical Engineering, Johns Hopkins University, Baltimore, MD 21210, USA
| | - Yun Chen
- Department of Mechanical Engineering, Johns Hopkins University, Baltimore, MD 21210, USA
| | - Sam Lee
- Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, MD 21210, USA
| | - Yu Wang
- Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, MD 21210, USA
| | - Saifeng Wang
- Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, MD 21210, USA
| | - Nate K Archer
- Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, MD 21210, USA
| | - William Andrews
- Department of Pharmaceutical Sciences, School of Pharmacy Mass Spectrometry Center, University of Maryland, MD 21201, USA
| | - Maureen A Kane
- Department of Pharmaceutical Sciences, School of Pharmacy Mass Spectrometry Center, University of Maryland, MD 21201, USA
| | - Erika Dare
- Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, MD 21210, USA
| | - Sashank K Reddy
- Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, MD 21210, USA; Department of Plastic and Reconstructive Surgery, Johns Hopkins School of Medicine, Baltimore, MD 21287, USA
| | - Zhiqi Hu
- Department of Plastic and Aesthetic Surgery, Nanfang Hospital of Southern Medical University, Guangzhou, Guangdong Province 510515, China
| | - Elizabeth A Grice
- Department of Dermatology and Microbiology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Lloyd S Miller
- Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, MD 21210, USA
| | - Luis A Garza
- Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, MD 21210, USA; Department of Cell Biology, Johns Hopkins University School of Medicine, Baltimore, MD 21210, USA.
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93
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Abstract
Human skin functions as a physical, chemical, and immune barrier against the external environment while also providing a protective niche for its resident microbiota, known as the skin microbiome. Cooperation between the microbiota, host skin cells, and the immune system is responsible for maintenance of skin health, and a disruption to this delicate balance, such as by pathogen invasion or a breach in the skin barrier, may lead to impaired skin function. Human skin functions as a physical, chemical, and immune barrier against the external environment while also providing a protective niche for its resident microbiota, known as the skin microbiome. Cooperation between the microbiota, host skin cells, and the immune system is responsible for maintenance of skin health, and a disruption to this delicate balance, such as by pathogen invasion or a breach in the skin barrier, may lead to impaired skin function. In this minireview, we describe the role of the microbiome in microbe, host, and immune interactions under distinct skin states, including homeostasis, tissue repair, and wound infection. Furthermore, we highlight the growing number of diverse microbial metabolites and products that have been identified to mediate these interactions, particularly those involved in host-microbe communication and defensive symbiosis. We also address the contextual pathogenicity exhibited by many skin commensals and provide insight into future directions in the skin microbiome field.
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94
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Dysbiosis and Enhanced Beta-Defensin Production in Hair Follicles of Patients with Lichen Planopilaris and Frontal Fibrosing Alopecia. Biomedicines 2021; 9:biomedicines9030266. [PMID: 33800045 PMCID: PMC7999846 DOI: 10.3390/biomedicines9030266] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 02/16/2021] [Accepted: 03/02/2021] [Indexed: 01/06/2023] Open
Abstract
Despite their distinct clinical manifestation, frontal fibrosing alopecia (FFA) and lichen planopilaris (LPP) display similar histopathologic features. Aberrant innate immune responses to endogenous or exogenous triggers have been discussed as factors that could drive inflammatory cascades and the collapse of the stem cell niche. In this exploratory study, we investigate the bacterial composition of scalp skin and plucked hair follicles (HF) of patients with FFA, LPP and alopecia areata circumscripta (AAc), as well as healthy individuals, in relation to cellular infiltrates and the expression of defense mediators. The most abundant genus in lesional and non-lesional HFs of LPP and FFA patients was Staphylococcus, while Lawsonella dominated in healthy individuals and in AAc patients. We observed statistically significant differences in the ratio of Firmicutes to Actinobacteria between healthy scalp, lesional, and non-lesional sites of FFA and LPP patients. This marked dysbiosis in FFA and LPP in compartments close to the bulge was associated with increased HβD1 and HβD2 expression along the HFs from lesional sites, while IL-17A was increased in lesional HF from AAc patients. The data encourage further studies on how exogenous factors and molecular interactions across the HF epithelium could contribute to disease onset and propagation.
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Ubags ND, Trompette A, Pernot J, Nibbering B, Wong NC, Pattaroni C, Rapin A, Nicod LP, Harris NL, Marsland BJ. Microbiome-induced antigen-presenting cell recruitment coordinates skin and lung allergic inflammation. J Allergy Clin Immunol 2021; 147:1049-1062.e7. [DOI: 10.1016/j.jaci.2020.06.030] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2019] [Revised: 06/02/2020] [Accepted: 06/04/2020] [Indexed: 12/17/2022]
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Constantinou A, Kanti V, Polak-Witka K, Blume-Peytavi U, Spyrou GM, Vogt A. The Potential Relevance of the Microbiome to Hair Physiology and Regeneration: The Emerging Role of Metagenomics. Biomedicines 2021; 9:biomedicines9030236. [PMID: 33652789 PMCID: PMC7996884 DOI: 10.3390/biomedicines9030236] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 02/22/2021] [Accepted: 02/23/2021] [Indexed: 12/18/2022] Open
Abstract
Human skin and hair follicles are recognized sites of microbial colonization. These microbiota help regulate host immune mechanisms via an interplay between microbes and immune cells, influencing homeostasis and inflammation. Bacteria affect immune responses by controlling the local inflammatory milieu, the breakdown of which can result in chronic inflammatory disorders. Follicular microbiome shifts described in some inflammatory cutaneous diseases suggest a link between their development or perpetuation and dysbiosis. Though the hair follicle infundibulum is an area of intense immunological interactions, bulb and bulge regions represent immune-privileged niches. Immune privilege maintenance seems essential for hair growth and regeneration, as collapse and inflammation characterize inflammatory hair disorders like alopecia areata and primary cicatricial alopecia. Current research largely focuses on immunological aberrations. However, studies suggest that external stimuli and interactions across the follicular epithelium can have profound effects on the local immune system, homeostasis, and cycling. Herein, we review hair follicle bacterial colonization, its possible effects on the underlying tissue, and links to the pathogenesis of alopecia, beyond the pure investigation of specific species abundance. As skin microbiology enters the metagenomics era, multi-dimensional approaches will enable a new level of investigations on the effects of microorganisms and metabolism on host tissue.
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Affiliation(s)
- Andria Constantinou
- Charité-Universitatsmedizin Berlin, Corporate Member of Freie Universitaet Berlin and Humboldt-Universitaet zu Berlin, Clinical Research Center for Hair and Skin Science, Department of Dermatology, Venereology and Allergy, Charitéplatz 1, 10117 Berlin, Germany; (A.C.); (V.K.); (K.P.-W.); (U.B.-P.)
| | - Varvara Kanti
- Charité-Universitatsmedizin Berlin, Corporate Member of Freie Universitaet Berlin and Humboldt-Universitaet zu Berlin, Clinical Research Center for Hair and Skin Science, Department of Dermatology, Venereology and Allergy, Charitéplatz 1, 10117 Berlin, Germany; (A.C.); (V.K.); (K.P.-W.); (U.B.-P.)
| | - Katarzyna Polak-Witka
- Charité-Universitatsmedizin Berlin, Corporate Member of Freie Universitaet Berlin and Humboldt-Universitaet zu Berlin, Clinical Research Center for Hair and Skin Science, Department of Dermatology, Venereology and Allergy, Charitéplatz 1, 10117 Berlin, Germany; (A.C.); (V.K.); (K.P.-W.); (U.B.-P.)
| | - Ulrike Blume-Peytavi
- Charité-Universitatsmedizin Berlin, Corporate Member of Freie Universitaet Berlin and Humboldt-Universitaet zu Berlin, Clinical Research Center for Hair and Skin Science, Department of Dermatology, Venereology and Allergy, Charitéplatz 1, 10117 Berlin, Germany; (A.C.); (V.K.); (K.P.-W.); (U.B.-P.)
| | - George M. Spyrou
- Bioinformatics ERA Chair, The Cyprus Institute of Neurology and Genetics, 6 Iroon Avenue, 2371 Ayios Dometios, Nicosia, Cyprus;
| | - Annika Vogt
- Charité-Universitatsmedizin Berlin, Corporate Member of Freie Universitaet Berlin and Humboldt-Universitaet zu Berlin, Clinical Research Center for Hair and Skin Science, Department of Dermatology, Venereology and Allergy, Charitéplatz 1, 10117 Berlin, Germany; (A.C.); (V.K.); (K.P.-W.); (U.B.-P.)
- Correspondence:
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97
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Nussbaum L, Chen YL, Ogg GS. Role of regulatory T cells in psoriasis pathogenesis and treatment. Br J Dermatol 2021; 184:14-24. [PMID: 32628773 DOI: 10.1111/bjd.19380] [Citation(s) in RCA: 121] [Impact Index Per Article: 40.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/26/2020] [Indexed: 12/14/2022]
Abstract
Psoriasis is a chronic inflammatory disease with a strong genetic component that can be triggered by environmental factors. Disease pathogenesis is mainly driven by type 1 and type 17 cytokine-producing cells which, in healthy individuals, are modulated by regulatory T cells (Tregs). Tregs play a fundamental role in immune homeostasis and contribute to the prevention of autoimmune disease by suppressing immune responses. In psoriasis, Tregs are impaired in their suppressive function leading to an altered T-helper 17/Treg balance. Although Treg dysfunction in patients with psoriasis is associated with disease exacerbation, it is unknown how they are functionally regulated. In this review, we discuss recent insights into Tregs in the setting of psoriasis with an emphasis on the effect of current treatments on Tregs and how already available therapeutics that modulate Treg frequency or functionality could be exploited for treatment of psoriasis.
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Affiliation(s)
- L Nussbaum
- Medical Research Council Human Immunology Unit, Radcliffe Department of Medicine, Oxford National Institute for Health Research Biomedical Research Centre, Medical Research Council Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - Y L Chen
- Medical Research Council Human Immunology Unit, Radcliffe Department of Medicine, Oxford National Institute for Health Research Biomedical Research Centre, Medical Research Council Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
| | - G S Ogg
- Medical Research Council Human Immunology Unit, Radcliffe Department of Medicine, Oxford National Institute for Health Research Biomedical Research Centre, Medical Research Council Weatherall Institute of Molecular Medicine, University of Oxford, Oxford, UK
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98
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Mesler AL, Benedeck RE, Wong SY. Preparing the hair follicle canal for hair shaft emergence. Exp Dermatol 2020; 30:472-478. [PMID: 33025661 DOI: 10.1111/exd.14210] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Revised: 09/15/2020] [Accepted: 09/30/2020] [Indexed: 12/17/2022]
Abstract
The emergence of hair is a defining event during mammalian skin development, but the cellular mechanisms leading to the opening of the hair follicle canal remain poorly characterized. Our previous studies have shown that early hair buds possess a central column of differentiated keratinocytes expressing Keratin 79 (K79), which marks the future hair follicle opening. Here, we report that during late embryogenesis and early postnatal development, K79+ cells at the distal tips of these columns downregulate E-cadherin, change shape, recede and undergo cell death. These changes likely occur independently of sebaceous glands and the growing hair shaft, and serve to create an orifice for hair to subsequently emerge. Defects in this process may underlie phenomena such as ingrown hair or may potentially contribute to upper hair follicle pathologies including acne, hidradenitis suppurativa and infundibular cysts.
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Affiliation(s)
- Arlee L Mesler
- Departments of Dermatology, and Cell and Developmental Biology, University of Michigan, Ann Arbor, MI, USA
| | - Rachel E Benedeck
- Departments of Dermatology, and Cell and Developmental Biology, University of Michigan, Ann Arbor, MI, USA
| | - Sunny Y Wong
- Departments of Dermatology, and Cell and Developmental Biology, University of Michigan, Ann Arbor, MI, USA
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99
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Abstract
T cell-mediated immune tolerance is a state of unresponsiveness of T cells towards specific self or non-self antigens. This is particularly essential during prenatal/neonatal period when T cells are exposed to dramatically changing environment and required to avoid rejection of maternal antigens, limit autoimmune responses, tolerate inert environmental and food antigens and antigens from non-harmful commensal microorganisms, promote maturation of mucosal barrier function, yet mount an appropriate response to pathogenic microorganisms. The cell-intrinsic and cell extrinsic mechanisms promote the generation of prenatal/neonatal T cells with distinct features to meet the complex and dynamic need of tolerance during this period. Reduced exposure or impaired tolerance in early life may have significant impact on allergic or autoimmune diseases in adult life. The uniqueness of conventional and regulatory T cells in human umbilical cord blood (UCB) may also provide certain advantages in UCB transplantation for hematological disorders.
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Affiliation(s)
- Lijun Yang
- Department of Immunology, School of Basic Medical Sciences, Peking University, NHC Key Laboratory of Medical Immunology (Peking University), Beijing, China
| | - Rong Jin
- Department of Immunology, School of Basic Medical Sciences, Peking University, NHC Key Laboratory of Medical Immunology (Peking University), Beijing, China
| | - Dan Lu
- Institute of Systems Biomedicine, Peking University Health Science Center, Beijing, China
| | - Qing Ge
- Department of Immunology, School of Basic Medical Sciences, Peking University, NHC Key Laboratory of Medical Immunology (Peking University), Beijing, China
- Department of Integration of Chinese and Western Medicine, School of Basic Medical Sciences, Peking University, Beijing, China
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100
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The Generation and Regulation of Tissue-Resident Tregs and Their Role in Autoimmune Diseases. J Immunol Res 2020. [DOI: 10.1155/2020/8815280] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Regulatory T cells (Tregs), as an important subset of T cells, play an important role in maintaining body homeostasis by regulating immune responses and preventing autoimmune diseases. In-depth research finds that Tregs have strong instability and plasticity, and according to their developmental origin, Tregs can be classified into thymic-derived Tregs (tTregs), endogenous-induced Tregs (pTregs), which are produced by antigen-stimulated T cells in the periphery in vivo, and induced Tregs (iTregs), which differentiate from naïve T cells in vitro. In recent years, studies have found that Tregs are divided into lymphatic and tissue-resident Tregs according to their location. Research on the generation and function of lymphoid Tregs has been more comprehensive and thorough, but the role of tissue Tregs is still in the exploratory stage, and it has become a research hot spot. In this review, we discuss the instability and plasticity of Tregs and the latest developments of tissue-resident Tregs in the field of biology, including adipose tissue, colon, skeletal muscle, and other Tregs that have been recently discovered as well as their production, regulation, and function in specific tissues and their role in the pathogenesis of autoimmune diseases.
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